Magneto-electric inductor.



.No. 880,485. PATENTED FEB. 25, 1908.

M. FISCHER.

MAGNETO ELECTRIC INDUGTOR. APPLICATION FILED JAN.10. 1905.

Snow doc 1 9 lime sacs MARTIN FISCHER, OF

MAGNETO- ELECTRIC INDUCTQR.

Specification of Letters Patent.

Patented Feb. 25, 1908.

.Original application filed July 6. 1900 Serial No. 22682- Divided and this application filed January 10. 1905. Serial No. 240.44].-

T 0 all whom it may concern:

Be it known that I, MARTIN FISCHER, a citizen of the Republic of Switzerland, residing at tric generators, comprising, broadly speaking, a permanent magnet, an armature between the poles thereof and arranged to close the magnetic circuit and consisting of a soft-iron core carrying an induction coil, in combination with means for controlling the direction of the magnetic flux with relation to the coil. This type of generator may be divided into two distinct classes, one in which the induction coil of the armature is adapted to rotate about its core, and the other in which a pole changer is adapted to rotate or oscillate about the armature. The first-named class of generators has been found practically useless for many purposes on account of the heavy massto be moved, as the coil must have'a sufficient number of ampere turns to produce current of requisite strength to perform the work in view, requirin comparatively great power, and the di 'cult in checking the momentum acquired y the coil in its periodical sudden angular movements. It has been proposed to avoid these difficulties by the use of a ole changer capable of rotating or' oscillatmg about the armature, but even in this construction the pole changer is of necessity of considerable weight, it being. enerally composed of a disk'at either end of t 1e arma ture and of soft iron segments connected to said disks, which latter are journaled in bearings in a. suitable support, means being provided to oscillate or rotate the pole chan er. Another arrangement is known in whic two armaturesare interposed between the poles of a permanent magnet and a rotatable or oscillatin" disk having soft iron segments is arranged to rotate or oscillate over the armature cores. In either case the weight of the pole changer is sufficiently great to render it diflicult. to overcome its momentum if operated -1nechanically to impart to it sudden angular or oscillatory movements, whilethe construction of either ZURICH, SWITZERLAND, ASSIGNOR TO AGTIENGESELLSOHAFT MAGNETA, OF ZURICH, SWITZERLAND.

class of generators is costly and more or less difficult.

' My improved generator is particularly designed for use in systems of time distribution in which current is sent to line at frequent predetermined periods, as for instance, every minute, and in which the pole changer is controlled by the master clock, as fully described and shown' in an a plication for atent filed by me July Stii, 1900, Ser. 0.

v22,582, of which the present'application is a division.

The object of this art of the invention is not only to simplify t 1e construction and reduce the cost of the generator to a minimum, but essentially to minimize the weight of the movable element thereof, and consequently its momentum, so that a power such as may be derived from a clock movement may be used to impart the aforesaid )erio'dical sudden movements to said movab e element and obviate the difficulties above referred to, due to the momentum of said movable element.

A characteristic feature of my invention, broadly speaking, lies in a stationary permanent magnet arranged to form an open magnetic circuit, in a stationary coil between the poles of said magnet, in a soft iron bar and in means to move the latter to close said circuit through thecoil. But that m invention may be fully understood, I wil de scribe the same in detail, reference being had to the accompanying drawings, in which- Figure 1 is an elevation, partly in section, of the preferred form of generator; Fig. 2 is a top plan view of Fig. 1, showing a modified arrangement of the magnetic poles, and also showing the continuous or loop circuit, in-- cluding a translating device.

Referring to Fi 1, M indicates thepermanent magnet, I P soft iron lates'secured to its oles, N, S, respective y, and p, p 19 p po e shoes havin 'concave faces, secure. to the upper and lower proximate ends of said plates. The pairs of pole shoes p, p, and p, 3 represent, respectively, divided poles of t is magnet M, having an open ma netic circuit.

indicates a soft iron core or field 018*- change'r which ispreferably cylindrica, as

its

shown in the figure referred to, and may be polygonal in cross-section, i. a, in the form of a fiat bar, and is mounted on or provided with suitable end journals to rotate on its longest axis between the pole-shoes, the faces of the latter being cylindrical in contour and of slightly greater diameter than that of the core, so that the latter may rotate close to the shoes but out of contact with them.

The core A is recessed or cut-away at diametrically opposite points where itextends between the pole-shoes, as shown at 21, the relative arrangement of the core and pole shoes being such that the magnetic flux will traverse the length of the core in opposite directions as the latter isrotated throu h angular distances of 180 degrees to close tie magnetic circuit. Thus, in the position indicated in Fig. 2 the magnetic flux will pass from the N-pole of the permanent magnet M through pole-shoe 19, through. the core A from the bottom to the top and from thence through the pole-shoe 79 to the S-pole of the magnet. Upon reversing the position of the core A, the flux from the N-pole will pass through the pole-shoe 19, through the core A in a direction the reverse of that just mentioned, to the pole-shoe p and the S-pole of the permanent magnet.

The stationary induction coil I is located in the magnetic field and circuit between the plates P, P, and surrounds the core A in such a position as to be in the path of the magnetic lines, so that upon a change of direction of the magnetic flux through the core A a current is roduced in the winding of said. coil.

As s own in Fig. 2, the terminals of the coil I are permanently secured to the conductors leading to a translating device, for instance, to the terminals of an electro-mag net M, whose armature oscillates a pawl acting on a ratchet wheel, for instance on the minute hand arbor of a secondary clock, the circuit in practice including .a number of such electro-magnets, as described in my pending application hereinab'ove referred to.

The advantages of a generator of electricity as above described are manifold. The coil, being stationary, may haveany desired number of ampere turns, the pole changer or circuit closer extending through the coil may be made very light as compared with the weight of the coil or with the weight of a polechangcr oscillating about the coil, which in systems of time distribution in which the current has to traverse comparatively great lengths of conductors, must have an adeq'uate number of ampere turns and is therefore quite bulky, while the construction ,of the generator is greatly simplified, as is obvious.

The pole charger or circuit closer A may be so geared or .otherwise connected to a prime mover as to impart angular movements in .M, shown in said Fig. 2.

one and the same direction to said pole changer, as for instance, through a pinion 19, the movements beingcontrolled by an arrester l, the pins 1 Z of which are engaged by a detent controlled by a time train of gearing; or said pole changer A may be so connected to the prime mover as to be oscillated as described in. my aforementioned application.

In the construction described, the direction of the currents generated is reversed at each change of olarity or closure of the magnetic circuit, but it will be readily understood that by the removal of the upper left hand pole shoe 1), Fig. 2', and the lower right hand ole shoe p supposed to be. removed in sai Fig. 2, impulses will be sent to line, which with some forms of translating devices may be found preferable or necessary, as in the ease of an ordinary electro-magnet By the provision of suitable mechanism whereby the field pole-changer D is caused to slowly recede from the magnetic poles and then to suddenly move backto its normal position, the armature is first de-polarized and its polarity suddenly restored, whereby currents are also generatedin the induction coil.

I do not limit my invention to the construction of generator shown and described, as

this may be variously modified without departing from the principle upon which its construction is based.

Having thus described my invention, what I claim as new therein and desire to secure by Letters Patent, is

1; A permanent magnet forming an open magnetic circuit, soft iron extensions secured to the magnet ends and ole pieces at the ends of the extensions a coil between the pole ieces and extensions, a soft iron bar extending through the coil and means to operate the bar to close the magnetic circuit between diagonally opposite poles, substantially as described. j

2. A permanent magnet having two pairs of pole pieces, a coil arranged between them and a soft iron bar passing through the coil to close the magnetic circuit first between one pair of diagonally opposite pole ieces and then between the other pair of iagonally opposite pole pieces, substantially as described.

3. A permanent magnet having soft iron pole extensions secured thereto, pole pieces' secured to the ends of the extensions, a coil between the extensions and pole )ieees, and a bar having oppositely directed laces at its ends, each face to cooperate with a pole piece whereby the magnet circuit will be close thereby between diagonally op osite pole pieces, substantially as described? 4. In a generator, the combination of a permanent ma not provided with forked pole pieces, a meta ic block rotatably mounted between said forkedpole pieces and a winding :arran ed in inductive relation "to said forked p0 e pieces and said metallic block,

substantially as described.

5. A Rermanent magnet formlng'an open magnetlcjcircuit, softiron extensions of said magnet and a pole iece at each end of said extensions therebyrmin founpoles, a coil iron bar of suitable form extending through the coil, and means to'rotate the bar to close themagnetic' circuit between diagonally opposite poles, substantiallyas described.

n of said magnet, a pole piece at each end I as described. extending between the pairs of poles, 'a seft of-said extensions, a coil located between the pole pieces and forming part of a closed electric circuit, a translating device also included in said circuit, a soft iron bar passing through the coil, and-means to rotate the bar to close the magnetic circuit through the coil-in directions that cross each other, substantially I In testimony thatl claim the foregoing as .my invention, 1- have signed my name in presence of two subscribing witnesses.

Witnesses; I

A. LIE RKNEG T,

BL M.

MARTIN FISCHER. i I 

